It is known to provide adjustable boring tools, as disclosed in U.S. Pat. No. 2,874,597, for example, with a cutter holder having a prismatic peripheral surface fitting a similarly shaped guiding bore in the boring tool body, such as to prevent relative rotation of the cutter holder within the guiding bore. However, manufacture of a cutter holder with a non-circular prismatic periphery and machining of a complementary similarly shaped bore in the boring tool body is a difficult, tedious and time consuming task.
The present invention provides an adjustable boring tool or boring head wherein the cutter holder is adjustably held in the boring tool body and is prevented from rotating around the axis of the holder in a manner much simpler than previously provided in the prior art. This is achieved, within the context of the present invention, by utilizing the wedge piece used for adjusting the position of the cutter for preventing axial rotation of a simple circularly cylindrical cutter holder disposed in a generally cylindrical bore in the boring tool body.